Re: [PATCH] net/pcap: fix indentation and numa node

[Stephen Hemminger <stephen@networkplumber.org>]

On Mon, 7 Apr 2025 10:51:37 +0100
Bruce Richardson <bruce.richardson@intel.com> wrote:

> On Sat, Apr 05, 2025 at 08:36:23AM -0700, Stephen Hemminger wrote:
> > The process private data allocation was indented incorrectly
> > in the source code, and had unnecessary cast. It is better
> > that the data be allocated on same numa node as the device
> > structure.
> > 
> > Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
> > ---
> >  drivers/net/pcap/pcap_ethdev.c | 13 ++++---------
> >  1 file changed, 4 insertions(+), 9 deletions(-)
> > 
> > diff --git a/drivers/net/pcap/pcap_ethdev.c b/drivers/net/pcap/pcap_ethdev.c
> > index 728ef85d53..aefa74c7be 100644
> > --- a/drivers/net/pcap/pcap_ethdev.c
> > +++ b/drivers/net/pcap/pcap_ethdev.c
> > @@ -1208,10 +1208,8 @@ pmd_init_internals(struct rte_vdev_device *vdev,
> >  	PMD_LOG(INFO, "Creating pcap-backed ethdev on numa socket %d",
> >  		numa_node);
> >  
> > -	pp = (struct pmd_process_private *)
> > -		rte_zmalloc(NULL, sizeof(struct pmd_process_private),
> > -				RTE_CACHE_LINE_SIZE);
> > -
> > +	pp = rte_zmalloc_socket(NULL, sizeof(struct pmd_process_private),
> > +				RTE_CACHE_LINE_SIZE, numa_node);
> >  	if (pp == NULL) {
> >  		PMD_LOG(ERR,
> >  			"Failed to allocate memory for process private");  
> 
> My concern there is that by forcing the numa node parameter, you are going
> to make it impossible to run with memory on the "wrong" numa node.
> Admittedly, this is less of a problem with virtual devices like pcap, than
> physical ones, but I still wonder if, on error, you should fallback to a
> regular "rte_malloc" call to allow the allocation to succeed so long as
> there is some hugepage memory available somewhere.
> 
> /Bruce

There already is a numa_node parameter on the eth dev, this was just trying
to put the private part on the same node as the existing eth dev.